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光肩星天牛对白桦林的危害及药剂防治效果 总被引：4，自引：0，他引：4
光肩星天牛(Anoplophroa glabripennis)是多种林木的重要蛀干害虫,根据国内文献(萧刚柔,1992;中国林业科学研究院,1983;山东林木昆虫志编委会,1993;李文杰等,1993;李亚杰,1983,山西省森林病虫害防治站,1986;杨秀元,1981,高瑞桐等,2000;安榆林,2006)等记述,光肩星天牛危害杨(Populus spp.)、柳(Salix spp.)、榆(Ulmus spp.)、糖槭(Acer saccharum)、桑树(Morus alba)、梨(Pyrus so.)、桦树(Betula sp.)、桤木(Alnus sp.)、悬铃木(Platanus sp.)、苹果(Malus sp.)、茶条槭(Acer ginnala)、元宝槭(Acer truncatum)、复叶槭(Acer negundo)、沙枣(Elaeagnus angustifolia). 相似文献
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以桑树(Morus alba L.)为试验材料,分别研究了200、500和1 000μmol·m-2 s-1光强下,不同浓度盐胁迫对桑树幼苗叶片活性氧(ROS)代谢和叶绿素荧光参数的影响。结果表明:桑树幼苗叶片的ROS代谢和叶绿素荧光特性明显受到光强的影响。200μmol·m-2 s-1和500μmol·m-2 s-1下,超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)有效降低了桑树幼苗叶片中的超氧阴离子(O2·-)和H2O2,且叶绿素荧光参数也没有发生明显变化,因此,弱光下桑树幼苗叶片抗氧化系统功能的增强在防止盐胁迫诱导的PSⅡ光抑制方面发挥了重要的作用。1 000μmol·m-2 s-1下,随着盐浓度的增加,桑树幼苗叶片O2·-大量产生,相应SOD活性增强,SOD的歧化作用导致了H2O2含量大量增加,同时在强氧化胁迫下,叶绿体内清除H2O2的APX活性却受到抑制,叶绿体内过量的H2O2可能破坏了电子传递链上的电子传递,并且PSⅡ发生了明显的光抑制。因此强光是引起盐胁迫下桑树幼苗叶片PSⅡ光抑制的重要原因之一,而强光引起盐胁迫下PSⅡ光抑制与ROS的代谢紊乱有关。 相似文献
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昆明市林工队苗圃地,雨季到来时,杂草生长迅速,种类繁多,单子叶杂草以熟地草(马唐)[Digitarla sanguinalis(L.)Stop]、香附子[Cyperus rotundus L.]和铁线草(狗牙根)[Cynodon dactylon(L.)Pers.]为主;双子叶杂草以辣子草[Galinsoga Parvif-lora.Caran]、曼陀萝(狗核桃)[Datura stra-manium L.]、荠莱[Capsella bursapastoris(L.)Med.]和野荞[Polygonum cymosumNeisn]为主,对苗木生长威胁很大,除草任务非常繁重。为节省劳力,及时消除草害,于1978年进行了苗圃地化学除草试验。 相似文献
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木豆 [Cajanus cajan( L.) Millsp]又名三叶豆、鸽子豆 ,为蝶形花科 ( Papilionoideae)木豆属 ( Cajanus)多年生的常绿灌木 ,是热带亚热带地区尤其是干热河谷地区荒山造林、退耕还林、改善生态环境的优良先锋树种[1 ] 。云南省已把木豆列为长江中上游防护林工程、澜沧江防护林工程、怒江防护林工程及天保工程的造林树种之一。目前中国林业科学研究院资源昆虫研究所已成功开发出木豆蛋白饲料 [2 ]、香酥木豆 [3]等用途 ,但由于木豆籽实在贮存期的主要害虫豆象[Callosobruchs maculates( F.) ]危害十分严重 (自然存放 3～ 5个月后 ,至少 80… 相似文献
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在六盘山香水河小流域的华北落叶松人工林样地,测定了2011年生长季降水转化过程中的大气降水、穿透水、干流、枯落物渗透水和主根系层(30 cm土层)土壤渗透水的pH值与多种阳离子的浓度及通量变化.结果表明:林外降水的pH值平均为7.13,转化为穿透雨和干流后降为6.73和6.00,转化为枯落物渗透水和土壤渗透水后回升为6.87和7.28.在降水转为由穿透雨和干流组成的林下降水后,绝大多数阳离子的浓度都不同程度地增大,但Zn2+浓度下降;虽然林冠截持使林下降水的数量减小,但由于雨水对林冠的离子交换及淋洗,林下降水的多数阳离子通量都比林外降水明显增大,K+、Mg2+、H+、Mn2+、Cu2+、Fe3+由林外的17.23、12.51、0.06、0.09、0.13、0.19 mmol·m-2分别上升到林下的141.87、32.93、0.10、0.68、0.24、0.56 mmol·m-2,但Na+、Ca2+、Zn2+的通量分别由林外的33.73、112.91、2.05 mmol·m-2减小为林内的30.70、75.75、1.10 mmol·m-2.在枯落物层渗透水中,绝大多数阳离子的浓度都不同程度地下降,仅Mg2+浓度微弱上升;受枯落物截持部分降水及雨水中阳离子与枯落物交换的影响,枯落物渗透水中所有阳离子的通量都比林下降水明显减小,K+、Na+、Mg2+、Ca2+、H+、Mn2+、Cu2+、Zn2+、Fe3+分别降至83.06、12.30、23.96、65.73、0.04、0.12、0.09、0.13、0.32 mmol·m-2.在主根系层土壤渗透水中,一些阳离子(K+、Mn2+、Cu2、Fe3+)的浓度下降,另一些阳离子(Na+、Mg2+、Ca2+、Zn2+)的浓度则上升,尤其Ca2+浓度显著上升;Na+、M2+、Ca2+、Mn2+、Zn2+的通量比枯落物渗透水增大,其值分别为37.49、62.83、202.41、0.22、1.05 mmol·m-2,但K+、Cu2+、Fe3+的通量比枯落物渗透水减小,其值分别为27.14、0.07、0.09 mmol·m-2.相对于林外降水的阳离子输入通量,林冠层对多数阳离子(除Na+、Ca2+、Zn2+)的通量为净淋出(增加)作用,枯落物层对多数阳离子(除K+、Mg2+、Mn2+、Fe3+)的通量为净固定(减少)作用,主根系层土壤对盐基离子(Na+、K+、Mg2+、Ca2+)和Mn2+的通量为净淋失(增大)作用,但对其他阳离子(H+、Cu2+、Zn2+、Fe3+)的通量为净固定(减少)作用. 相似文献
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Summary Six African hardwoods (Nauclea diderrichii, Chlorophora excelsa; Lovoa trichilioides; Gosswailerodendron balsamiferum; Bombax buonopozense and Hevea brasiliensis) were ashed. The percentage ash content of the woods was determined, and the ash samples were analyzed for soluble base (as K2CO3); Na+, K+, Ca2+, Mn2+ and Fe3+. 相似文献
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Kraft lignins modified by radical sulfonation or alkaline oxygen treatment were rich in acidic groups, such as sulfonic acid,
carboxylic acid, and phenolic hydroxyl groups, and were effective as soil-conditioning agents, especially because of their
ability to trap aluminum ions eluted from soil under acidic conditions. Formation of complexes between aluminum ions and modified
lignins was examined using potentiometric titration and 27Al nuclear magnetic resonance (NMR) spectroscopy. Changes in the titration curve of a modified lignin by the addition of aluminum
ions suggest the release of protons after the formation of complexes between them. Disappearance of 27Al-NMR signals assigned to various aluminum ions by the addition of kraft lignin treated with alkaline oxygen was also attributed
to the formation of complexes. The relative ease of proton release because of complex formation between a modified lignin
and metal ions was as follows: Fe3+ > Al3+ > Cu2+ > Pb2+ > Mn2+ > Ca2+. This indicates that aluminum complexes are quite stable, and the aluminum ion is not exchanged with cations other than Fe3+.
Received: October 24, 2001 / Accepted: January 16, 2002
Present address: Asian Natural Environmental Science Center, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan Tel. +81-3-5841-7506;
Fax +81-3-5841-5230 e-mail: ukyoko@mail.ecc.u-tokyo.ac.jp
Part of this study was presented at the 11th International Symposium on Wood and Pulping Chemistry, Nice, June 2001
Correspondence to:K.S. Katsumata 相似文献
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Summary The ashes of some medicinally used tropical woods were characterised. These were Afzelia africana, Alstonia congensis, Antiaris africana, Terminalia ivorensis, Azadirachta indica, Ricinodendron heudelotti, Chlorophora excelsa and Daniellia ogea. The ashes were obtained by treating wood in a muffle furnace, after which the ashes dissolved in distilled water. The very alkaline solutions obtained were analysed for Na+, K+, Ca2+, Mg2+, Mn2+, Fe2+, Cu2+, Cl-, SO
4
2-
and PO
4
3-
. Due to wide medicinal application of these wood species experiments were made to determine the cations and anions which may be active ingredients in the compounds (drugs) used in the treatment of differet ailments.The authors are thankful to A. Amusan of Soil Science Department, Obafemi Awolowo University, Ile-lfe for technical assistance 相似文献
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在不同条件下对越橘红色素稳定性的研究结果表明:越橘红色素热稳定性较差、温度对其影响明显,在70℃时,越橘红色素会受到一定影响;45℃以下低温避光条件下,稳定性较好;低pH值稳定性较好,添加异抗坏血酸钠、三聚磷酸钠可提高越橘红色素的稳定性;金属离子Fe2+和Cu2+使越橘红色素的颜色改变或发生明显的沉淀,而Pb2+、Al3+、Zn2+、Mg2+、Mn2+影响较小。 相似文献
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《Fitoterapia》2014
Mulberry leaf, an important traditional Chinese medicine, possesses many biological activities, including effects of anti-obesity. However, which constituents of mulberry leaf are responsible for its anti-adipogenic action is unclear. This study primarily investigated the chemical constituents from mulberry leaf and their bioactivity on the proliferation and differentiation of 3T3-L1 preadipocytes. A new flavane derivative, (2S)-4′-hydroxy-7-methoxy-8-prenylflavan (1), together with twelve known compounds including three flavanes (2–4), three chalcones (5–7), two flavones (8–9), two benzofurans (10–11) and two coumarin (12–13) was isolated from mulberry leaf. The structure of the new compound was elucidated by various spectroscopic methods including UV, HR-ESI-MS, 1H and 13C NMR and CD. The results of activity screening showed that compound 2, 6 and 7 inhibited the proliferation and differentiation of 3T3-L1 preadipocytes. 相似文献
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１９９８年４月至１９９９年３月对广州市白云山马尾松林和常绿阔叶林、广州市龙眼洞马尾松林两试验点进行了酸雨的监测,并测定和分析了林内穿透雨物理量及化学量,旨在探讨酸雨对不同森林冠层养分淋溶规律的影响。结果表明：（１）广州市酸雨占次数的７９．７％或占降雨量的９５．１％。（２）酸雨通过林冠层后,ｐＨ值明显增加。（３）在马尾松林和常绿阔叶林中,某些单次降雨出现ＳＯ４＾２－、ＮＯ３＾－、ＮＨ４＾＋Ａｌ＾３＋、Ｎａ＾＋的负淋溶现象,说明森林对这些离子（特别是ＮＯ３＾－、Ａａ＾３＋）具有吸收作用;阔叶林全年的ＮＯ３＾－和Ａｌ＾３＋净淋溶为负值,说明阔叶林比马尾松林对这两种离子具有更强的吸收能力。（４）雨水酸度增加（即ｐＨ值减小）,明显提高阳离子Ｃａ＾２＋、Ｍｇ＾２＋、Ｋ＾＋和Ｎａ＾＋冠层淋溶面分率。（５）ＮＨ４＾＋、ＳＯ４＾ 相似文献
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In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production
or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of
paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for
estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age
from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as
independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during
the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry
was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches
were pruned back, rice yields could be maintained if the paper mulberry stem density was <0.22 stems m−2, suggesting that if paper mulberry is managed properly, rice yields can be maintained at current levels. The paper mulberry-upland
rice rotation system improves the productivity of a traditional slash-and-burn system through harvesting paper mulberry inner
bark; however the long-term sustainability of such a system remains unclear and warrants further investigation. 相似文献
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杜鹃花是世界名花,属于中国十大名花之一,具有极高的观赏价值,在国际上广泛应用于园林绿化。花色是杜鹃花重要的观赏特性,也是一种与传粉者和自然环境的适应性特征,杜鹃花色素主要包含花青素苷和黄酮醇,其种类、含量和相关基因对花色形成具有重要影响,研究花色素组成及相关的生物合成途径是杜鹃花色育种的关键。文中综述了国内外对杜鹃花色素组成、花色遗传特性与育种、花青素苷合成途径等研究现状,揭示了杜鹃花色形成原理,提出未来研究重点为:注重黄色、花斑品种和蓝色杜鹃花培育,揭示杜鹃花中类黄酮着色机理及调控因子,运用转录组、代谢组、全基因组等新一代测序技术探究杜鹃花色素并建立相关数据库,以期为杜鹃花色研究提供参考。 相似文献
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The study was carried out over a period of 1999–2003 in the Dupniański Stream catchment located in Silesian Beskid Mts. Region
(Southern Poland). Analysis of the chemical composition of bulk precipitation, throughfall, stemflow, surface flow, soil water
(horizontal + vertical and vertical penetration) and outflow water samples was performed. The complex data matrix with more
than 3,000 observations of water reaction, major anions (F−, Cl−, NO3
−, SO4
2−) and cations (NH4
+, Na+, K+, Ca2+, Mg2+, Fe2+, Mn2+ and Zn2+) were treated by regression modelling. The modelling approach took into account seasonal variability according to winter
and growing season, as well as chronosequence of spruce stands. The retention of considerable levels of contaminants by the
canopy, and their removal or washout from needles by rainfall caused changes in the concentration of anions and cations reaching
the soil surface compared to the concentrations in bulk precipitation. In the youngest stand, most elements except NH4
+, SO4
2− and K+ were retained in the canopy, and even H+ ions were neutralized. In the older stands, most elements increased in net throughfall fluxes, and the acidity increased
strongly. Soil water was slightly correlated with throughfall, while outflow water showed no correlations with the above ground
water flows, and seemed to depend mostly of the bedrock. 相似文献